Methanol energy content

From a prachcal standpoint, formic acid or its salts are the least valuable reaction products. The energy content of formic acid upon its reverse oxidation to CO2 is insignificant, and its separation from the solutions is a labor-consuming process. At present, maximum effort goes into the search for conditions that would ensure purposeful (with high faradaic yields) synthesis of methanol, hydrocarbons, oxalic acid, and other valuable products. 

The energy content per mole of methanol, in terms of AG° for the overall process ... 

The butanols and their methyl and ethyl ethers have several advantages as oxygenates over methanol and ethanol in gasoline blends. Their energy contents are closer to those of gasoline the compatibility and miscibility problems with petroleum fuels are nil excessive vapor pressure and volatility problems do not occur and they are water tolerant and can be transported in gasoline blends by pipeline without danger of phase separation due to moisture absorption. Fermentation processes (Weizmann process) have been developed for simultaneous production of 1-butanol, 2-propanol, acetone, and ethanol from... 

One of the chief drawbacks of methanol, and one that has essentially precluded its wide use in internal-combustion engines, is its low energy content. 

Methanol is a liquid fuel that is readily dispensed and stored but, compared with conventional liquid fuels, is by no means ideal it is both toxic and water-miscible and has an energy content per litre that is well below that of petrol see Table 1.4, Chapter 1. A further drawback of incorporating a reformer into the vehicle is the need to supply heat for its operation. At 80-90 °C, the waste heat from the fuel cell would be inadequate and it would be necessary to burn some of the methanol to provide the heat or to use electrical heating. Either of these two options would obviously reduce the effective efficiency of the fuel-cell system. Altogether, on-board methanol reformers pose as many engineering problems as on-board hydrogen storage. Furthermore, the combined cost of a reformer and a fuel cell is likely to prove prohibitive, at least for small vehicles such as cars. 

The Direct Methanol Fuel Cell, DMFC, (see Fig. 7-6 in section 7.2.2.4.) is another low temperature fuel cell enjoying a renaissance after significant improvements in current density. The DMFC runs on either liquid or, with better performance but higher system complexity, on gaseous methanol and is normally based on a solid polymer electrolyte (SPFC). R-Ru catalysts were found to produce best oxidation results at the anode, still the power density is relatively low [5, 29]. Conversion rates up to 34 % of the energy content into electricity were measured, an efficiency of 45 % is expected to be feasible in the future. SPFC in the power order of several kW to be used in automobile applications are currently in the development phase. 

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